Outrigger support mechanism

ABSTRACT

An outrigger support mechanism for stabilizing load-lifting apparatus and the like which includes a frame, a beam telescopingly mounted within the frame, and an arm pivotally connected to the outer end of the beam. A first power means is provided for extending and retracting the beam relative to the frame, and a second power means is provided for pivoting the arm relative to the beam between an upward transport position and downward support positions.

United States Patent 1191 1111 3,843,154 Thompson Oct. 22, 1974OUTRIGGER SUPPORT MECHANISM 3,638,965 2/1972 Cassady 280/l50.5 Inventor:Clarence Russell Thompson, I 3,734,531. 5/1973 Mettuller 280/1505Waverly Iowa I Primary Examiner-Robert R. Song [73] Asslgneez KoehringCompany, Milw e, Attorney, Agent, or Firm-Finnegan, Henderson,

Farabow & Garrett [22] Filed: 1 Nov. 1, 1972 [21 Appl. N0; 302,813 [57]ABSTRACT An outrigger support mechanism for stabilizing loadliftingapparatus and the like which includes a frame, CCll. a beamtelescopingly mounted within the frame and [58] Fie'ld 6 R H an armpivotally connected to the outer end of the 1 beam. A first power meansis provided for extending and retracting the beam relative to the frame,and a second power means is provided for pivoting the arm [56]References and relative to the beam between an upward transport po-UNITED STATES PATENTS sition and downward support positions. 3,007,71711/1961 NOly 280/1505 3,396,854 8/1968 Crisp 212/145 21 Clam, 5 DrawmgFigures lii li'iliiii 0:122 1924 I iAIENTEB m a at 2 3.843. 1 54 FIELDOF THE INVENTION The present invention relates to an outrigger supportmechanism for stabilizing load lifting apparatus and the like. Theoutrigger support mechanism of the present invention is particularlyuseful for stabilizing vehicles such as mobile cranes, log loaders, andother devices which are top-heavy and/or subject to off-center loadingduring usage.

BACKGROUND OF THE INVENTION It has been commonplace to fit mobile cranesand similar devices with outrigger support mechanisms. Typically, fouroutriggers, one located near each corner of the device, are employed toprovide stability and to prevent tipping during usage.

The Outriggers of the prior art have often been relatively cumbersome,awkward, inefficient and incapable of use in certain locations. Previousoutriggers have been unduly restrictive in the amount of lateral anddownward extension possible, and have often required a certain amount ofmanual adjustments which are both time-consuming and, in some instancesdangerous.

Vehicles such as mobile cranes are frequently operated in locationswhere the terrain in the vicinity of use of the vehicle is not flat.Under such conditions, many of the outrigger devices of the prior artlack sufficient versatility with respect to the support positions theywill assume. With such prior art outriggers, adequate support can onlybe obtained with great difficulty, as by providing blocks for thesupport arms or making manual adjustments.

' Outriggers have. been provided with power means for moving thesupports from inoperative transport position to operative supportpositions. However, many of such devices are not capable of beingretracted to as narrow a minimum transportation width as is desirable.In addition, generally the power means for such devices are located sothat they are subject to be damaged, particularly by falling objects.

The outrigger device of the present invention, wh'ile capable ofretraction to a narrow transportation width, may be placed in any of alarge variety of support positions. The preferred outrigger may be usedto raise the entire supported device above ground level and is capableof supporting and stabilizing devices on rough or uneven terrain. Inaddition, because of the wide range of supportpositions which may beselected, the outrigger of the present invention may be employed when itis necessary to place the supported device near obstructions.

In the preferred embodiments, the outrigger device of the presentinvention also provides protection for the power means for moving theoutrigger from a transport position to various support positions.

SUMMARY OF THE INVENTION The present invention is directed to anoutrigger support mechanism for stabilizing load-lifting apparatus andthe like. The outrigger support mechanisms of the present invention areparticularly suitable for use with vehicles such as mobile cranes, logloaders, and similar devices. The outrigger of the present invention hasa support arm having an outer end. The support arm is pivotal between atransport position in which the outer end of the arm is upwardlydisposed, and support positions in which the outer end of the arm isdownwardly disposed. In accordance with one embodiment of the presentinvention, the outrigger includes a groundengaging pad and pivot meansfor the pad connecting the pad to the outer end of the arm. The pivotmeans allows the pad to rotate inwardly of the arm when the arm is inthe transport position. Such a feature results in a substantial decreasein the transport width of the outrigger, and is particularly significantwith respect to use with mobile vehicles.

In another embodiment of the present invention, means are provided formoving the support arm to a plurality of operative support positionsbetween the transport position and the maximum downward supportposition. The operative support positions cover a large area extendingvertically outward and downward from the supported device. A widelatitude of possible support positions is particularly advantageous foruse in stabilizing devices near obstructions or on uneven terrain.

The outrigger support mechanism of a preferred embodiment of the presentinvention includes a frame, a beam telescopingly mounted within theframe, and an arm pivotally connected to the outer end of the beam. Inaccordance with one embodiment of the present in- .vention, the beam issubstantially horizontally disposed and a substantially horizontallydisposed power means is provided for extending and retracting the beamrelative to the frame. A second substantially horizontally disposedpower means also is provided for pivoting the arm relative to the beambetween an upward transport position and downward support positions.Preferably, the first and second power means are vertically aligned.

In accordance with a further preferred embodiment of the presentinvention, in which the support mechanism includes a frame, a beamtelescopingly mounted in the frame, an arm pivotally connected to theouter end of the beam, and a first power means for extending andretracting the beam relative to the frame, a second power means locatedwithin the frame at least when the arm is in the transport position, isprovided for pivoting the arm relative to the beam between an upwardtransport position and downward support positions. Preferably, the firstpower means also is located within the frame. The beam may be hollow andthe second power means may be located within the beam as well as withinthe frame. By placing the power means within the frame, the power meansare protected from being damaged, such as by being struck by fallingobjects.

In addition, in accordance with a further preferred embodiment of thepresent invention, in which the outrigger support mechanism includes aframe, a beam telescopingly mounted in the frame, an arm pivotallyconnected to the outer end of the beam,.and a first power means forextending and retracting the beam relative to the frame, a second powermeans is provided for pivoting the arm relative to the beamindependently of the extension position of the beam. The second powermeanspermits pivoting of the arm from an upward transport position toany of a plurality of outward operative downward support positionsbetween the transport position and support positions in which the arm isin the maximum downward position. Preferably, the beam also may beextended and retracted independently of the position of the support arm.In accordance with this embodiment, the outrigger may provide supportinany of a wide range of positions.

BRIEF DESCRIPTION OFTHE DRAWINGS FIG. 1 is a fragmentary side view of acrane truck having outrigger beams embodying features of the presentinvention.

FIG. 2 is a side view of an outrigger support mechanism embodyingfeatures of the present invention with parts of the frame andtelescoping beam broken away to show internal construction. In FIG. 2the fully lined illustration shows the ground-engaging pad in theretracted inward transport position while the phantom illustrations showvarious support positions.

FIG. 3 is similar to FIG. 2, showing both the beam and the arm inextended positions. I

FIG. 4 isan end view of an outrigger support mechanism embodying variousfeatures of the present invention.

FIG; 5 is a fragmentary detail top view, with the frame and beam cutaway, showing the connection between the beam and power means inaccordance with one embodiment of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The outrigger support mechanismof the present invention may be employed for stabilizing load-liftingapparatus and the like. The support mechanism is particularly useful tostabilize vehicles such as mobile cranes, etc. The crane truck shownherein in FIG. 1, by way of example, has a conventional chassis or framewith the usual drivers cab 12 over the front wheels 14 and a revolvablemachinery platform and operators cab 16. The machine platform andoperators cab is mounted on a turntable 18 over the rear wheels 20.While in the embodiment illustrated, the chassis 10 is supported onground-engaging pneumatic tires 14 and 20, it will be appreciated thatother types of ground support, such as crawler'treads, etc., could beemployed.

As embodied in FIG. 1, the chassis 10 is provided with outrigger supportmechanisms, indicated generally at 22, to the rear of the front wheels14 andto the rear of the rear wheels 20. The crane truck of FIG. I isprovided with four outrigger support mechanisms embodying features ofthe present invention, extending traversely across chassis 10 at itsunder-surface. The outriggers, each of which are substantiallyidentical, are shown in greater detail in FIGS. 2 through 5.

The outrigger support mechanism of the present invention includes asupport arm having an outer end, which arm is pivotal between atransport position in which the outer end of thearm is upwardlydisposed, and support positions in which the outer end of the arm isdisposed downwardly relative to the transport position. In accordancewith one embodiment of the present invention, the mechanism is providedwith a ground-engaging pad and pivot means for the pad con necting tothe outer end of the arm. The pivot means allow the pad to rotateinwardly of the arm when the arm is in the transport position.

In the embodiment shown in the drawings, the outrigger support mechanismis provided withan elongated arm 24. A ground-engaging pad 26 ispivotally secured to the outer end of arm 24 by pivot pin 28 In FIG. 1,the fully lined illustration of FIG. 2, and FIG. 4, support arm 24 andpad 26 are shown in the upward transport position. A support position inwhich arm 24 is downwardly disposed is illustrated in FIG. 3. As shownin FIG. 1, the fully lined illustration of FIG. 2, and FIG. 4,ground-engaging pad 26 may be rotated about pin 28 so that pad 26 isdisposed inwardly of arm 24 when the arm is in the transport position.Preferably, a second pivot pin (29 of FIG. 4), perpendicular to pivotpin 28, is interposed between pad 26 and pin 28 to provide a universalmovement of pad 26 relative to arm 24. Universal action of pad 26 allowsit to adjust to the contour of the supporting surface.

In accordance with another embodiment of the present invention, in whichan outrigger support mechanism is provided having a support arm pivotalbetween an upwardly disposed transport position and support positions inwhich the arm is downwardly disposed, power means are provided formoving the arm to a plurality of operative support positions between thetransport position and maximum downward support positions.

As here embodied, a plurality of downward support positions are shown inthe phantom illustrations of FIG. 2. The cross-hatched portion of thedrawing, generally 30, illustrates the position range of the groundsupport pad, measured from the center point of pivot pin 28. The centerpoint of pin 28 can be placed in a support position anywhere within thecross-hatched area 30.

Preferred means for moving the support arm to any of the supportpositions will be described subsequently.

In accordance with preferred embodiments of the present invention, theoutrigger support mechanism includes a frame, a beam telescopinglymounted in the frame, and an arm pivotally connected to the outer end 1of the beam.

could comprise a pair of lateral members in juxtaposition, a U-shapedmember, a yolk, etc. v

In the present embodiment, an elongated hollow, horizontally disposedbeam 34 -is telescopingly mounted within frame 32. Beam 34 may beextended outwardly from frame 32, and after extension, retracted backinto frame 32. Arm 24 is pivotally connected at pivot pin 36 to theouter end of beam 34. Arm 24 may be pivoted about pin 36 from theupwardly disposed transport position shown in, e.g., the solid linedillustration of FIG. 2, to downward support positions such as shown inthe phantom illustration of FIG. 2.

As shown in FIGS.1 and 4, frame 32 may be used in connection with morethan one beam and support arm. A beam carrying a support arm may extendfrom either end of the frame to provide support on opposite sides of thedevice to be stabilized.

In accordance with preferred embodiments of the present invention, theoutrigger support mechanism is provided witha first power means forextending and retracting the beam relative to the frame. In addition,the outrigger is provided with a second power means for pivoting the armrelative to the beam between an upward transport position and downwardsupport positions..The expression downward support positions, as usedherein, refers to support positions in which the support arm is orienteddownward, relative to the transport position.

In the embodiment shown in the drawings, the first power means comprisesan extensible and retractable double-acting hydraulic cylinder 38. Asembodied, cylinder 38 is substantially horizontally disposed and locatedwithin frame 32. One end of cylinder 38 is connected to frame 32 throughrod 40; the opposite end of cylinder 38 is connected to beam 34 throughrod 44.

As here embodied, the second power means comprises an extensible andretractable hydraulic cylinder 42. Hydraulic cylinder 42 issubstantially horizontally disposed and located within beam 34. Cylinder42 is also located within frame 32 when the outrigger support mechanismis in the transport position (FIG. 2). One end of hydraulic cylinder 42is connected to beam 34 by pivotal attachment to rod 44. The other endof cylinder 42 is pivotally connected to arm 24 at pivot pin 46.

Hydraulic cylinders 38 and 42 are independently connected withconventional fluid pressure sources and a fluid reservoir (not shown) sothat the cylinders may be extendedand retracted by operation ofconventional hydraulic controls (not shown).

In operation, the support arm of the outrigger of the present inventionmay be moved between the transport position and a plurality of operativesupport positions intermediate to the transport position and maximumdownward support positions. In accordance with a preferred embodiment ofthe present invention, the beam may be moved inwardly or outwardly ofthe frame, independently of the position of the support arm. Similarly,the support arm may be moved between the transport position and supportpositions, without regard to the position of the beam.

In the embodiment shown in the drawings, beam 34 may be extendedoutwardly from frame 32 by actuating hydraulic cylinder 38. Whencylinder 38 is extended from a contracted position (shown in FIG. 2) toan extended position (shown in FIG. 3) force will be exerted againstrods 40 and 44 causing beam 34 to slide outwardly from frame 32 in alongitudinal direction. Similarly, when cylinder 38 is retracted, beam34 will be retracted into frame 32. Movement of beam 34 is not dependentupon the position of arm 24.

As further shown in the embodiment ofthe drawings, arm 24 may bearticulated about pivot pin 36 by actuation of cylinder 42. Whencylinder 42 is extended from a contracted position (shown in FIG. 2) toan extended position (shown in FIG. 3) force will be exerted againstrods 44 and pivot pin 46. Cylinder 42 will pivot about rod 44 in aslightly upward direction and arm 24 will pivot downwardly about pivotpin 36. Similarly, when cylinder 42 is retracted, arm 24 pivots upwardlytowards the transport position shown in'FlG. 2. As is apparent, movementof arm 24 is not dependent upon the position of beam 34.

With specific reference to the phantom illustrations of FIG. 2, whenbeam 34 is fully retracted, arm 24 may be pivoted downwardly until thecenter point of pivot pin 28 is in support position A. Arm 24 may befurther pivoted to support position B or to any intermediate supportposition on the arm between A and B. Similarly, with beam 34 fullyextended, arm 24 may be pivoted downwardly so that the center point ofpivot pin 28 is in support position C. Arm 24 may be further pivoted tomaximum downward support position D or to any intermediate position onthe are between C and D. It will be appreciated that arm 24 cansimilarly be pivoted, by means of cylinder 42, to various supportpositions when beam 34 has been extended to positions intermediate theextreme retracted position shown in FIG. 2 and the extreme extendedposition shown in FIG. 3. In this manner, support can be provided withthe center point of pivot pin 28 located anywhere within thecross-hatched area of FIG. 2. Thus, the operator can select a desiredsupport position from a wide variety of possible support positions.Selection of a particular support position will of course, be dependentupon obstructions, terrain, etc. in the area of the device beingstabilized.

To place the outrigger in the transport position after usage, cylinders38 and 42 are retracted, causing beam 34 to retract into frame 32 andarm 24 to pivot upwardly. Ground-engaging pad 26 may be rotated inwardlyof arm 24 (as shown in the fully lined illustration of FIG. 2) toachieve minimum overall transportation width.

In FIG. 2, the ground line is shown at 48. This represents the plane, onflat terrain, upon which the device to be stabilized would rest. Forexample, ground line 48 could represent the plane upon which the tiresof a crane truck would set. As shown in FIG. 2, arm 24 and pad 26 may bepositioned below the normal ground line. Such a feature allows thestabilized device to be lifted entirely off of the ground by theoutrigger support mechanism. In addition, such a feature allows forsupport in areas where the ground falls away from the device beingstabilized. As an example, it is often necessary to support crane trucksand the like on narrow, raised road beds. Under such conditions, supportcan only be obtained by moving support arms to a level below the levelat which the wheels of the vehicle rest.

Preferably, cylinder 38 is equipped with check valves which lock oil inthe cylinder so that support of arm 24 is not dependent on hoses,fittings, other valves in the system, etc. Such a safety feature permitsall hydraulic connections to the cylinder to be removed without losingsupport to the arm.

The invention in its broader aspects is not limited to the specificdetails shown and described and departures may be made from such detailswithout departing from the principles of the invention and withoutsacrificing its chief advantages.

What is claimed is:

1. In an outrigger support mechanism for stabilization of a vehicle,said outrigger having a support arm, which arm has an inner end and anouter end, said arm being pivotal between a transport position in whichsaid outer end of said arm is upwardly disposed and support positions inwhich said outer end of said arm is disposed downwardly from thetransport position, the improvement comprising a ground-engaging padhaving a ground contacting surface, pivot means connecting said paid tothe outer end of said arm and means for extending and retracting saidarm toward and away from said vehicle and for effecting movement of saidarm and pad from (1) said transport position wherein said groundcontacting surface is disposed on one side of a plane including saidpivot means and said inner end to (2) said support positions whereinsaid ground contacting surface is disposed on the other side of saidplane.

2. The outrigger of claim 1 including supporting means for said'supportarm, said inner end being pivotally attached to said support means, andwherein the arm and pad moving means comprises power means pivotallyconnected to said arm to effect rotation of said arm about said innerend from said transport position to said support positions.

3. An outrigger support mechanism comprising:

A. a frame;

B. a substantially horizontally disposed beam telescopingly mountedwithin said frame;

C. an arm pivotally connected to the outer end of said beam;

D. a first power means for extending and retracting said beam relativeto said frame, and;

E. a second power means for pivoting said arm relative to said beambetween an upward transport position and downward support positions,each of said first and second power means being independently operable.

4. The outrigger of claim 3 in which said first and second power meansare coplanar.

5. A load-lifting apparatus including at least one outrigger supportmechanism of claim 3.

6. The outrigger of claim 3 in which said first power means is locatedwithin said frame.

7. An outrigger support mechanism comprising:

A. a frame;

B. a beam telescopingly mounted in said frame;

C. an arm pivotally connected at one end to the outer end of said beam,said arm having a groundengaging pad including a ground contactingsurface on the other end thereof;

D. a first power means for extending and retracting said beam relativeto said frame; and

E. a second power means for pivoting said arm relative to said beambetween an upward transport position and downward support positions,said second power means being located with said frame at least B. a beamtelescopingly mounted in said frame;

C. an armpivotally connected to the outer end of said beam;

D. a first power means for extending and retracting said beam realtiveto said frame;

E. a second power means for pivoting said arm relative to said beam,independently of the extension position of said beam, from an upwardtransport position to any of a plurality of operative downward supportpositions between said transport position and support positions in whichsaid arm is in the maximum downward position.

14. The outrigger of claim l3/irrWhTch said first power means providesfor/e ension and retraction of said beam independentiy of the positionof said arm.

15. The outrigger of claim 13 in which said beam,

' said first/power means, said second power means, are

when said arm is in the transport position and being operableindependent of said first power means wherein said arm is movablebetween said transport and support positions independent of the positionof said beam; when said arm is in said transport position, the groundcontacting surface of said pad is disposed on one side of a planeincluding said arm one end and other end and when said arm is in saidsupport positions, the ground contacting surface is disposed on theother side of said plane.

8. The outrigger of claim 7 in which said first power means is locatedwithin said frame.

9. The outrigger of claim 8 in which said first and second power meansare coplanar.

10. The outrigger support mechanism of claim 7 in which said beam, saidfirst power means, and said second power means are substantiallyhorizontally disposed.

ll. The outrigger of claim 7 in which said beam is hollow and saidsecond power means is located within said beam.

12. A load lifting apparatus including at least one outrigger supportmechanism of claim 7.

13'. An outrigger support mechanism comprising:

A. a frame;

substantially horizontally disposed.

16. The outrigger of claim 15 in which said first and second power meansare coplanar.

17. The outrigger support mechanism of claim 13 in which said firstpower means is located within said frame, and said second power means islocated within said beam.

18. A load lifting apparatus including at least one outrigger supportmechanism of claim l3.

19. An outrigger support mechanism for stabilization of a vehicle, theoutrigger comprising a support arm, pivotal means connecting said arm toan arm supporting means, power means for selectively moving said armbetween (a) a transport position in which said arm is disposed above apredetermined position of said vehicle and (b) a plurality of operativesupport positions in which said arm is disposed at different levelsbelow said portion of said vehicle, and laterally between (0) a proximalposition in which said arm is adjacent to said vehicle and (d) a distalposition in which said arm is remote from said vehicle, and meansenabling said power means to move said arm between said transportposition and said support positions independent of the lateral positionof said arm.

20. An outrigger support mechanism as defined in claim 19 whereinsaid'power means comprises first reciprocating means attached to saidarm supporting means for moving said arm supporting means laterallybetween said proximal and said distal positions and second reciprocatingmeans attached to said support arm for moving said support arm betweensaid transport and support positions.

21. An outrigger support mechanism comprising:

a. a frame;

b. a substantially horizontally disposed beam telescopingly mountedwithin said frame;

c. an arm pivotally connected to the outer end of said beam;

d. a ground-engaging pad having a ground contacting surface and beingpivotally connected to said arm;

being independently operable.

1. In an outrigger support mechanism for stabilization of a vehicle, said outrigger having a support arm, which arm has an inner end and an outer end, said arm being pivotal between a transport position in which said outer end of said arm is upwardly disposed and support positions in which said outer end of said arm is disposed downwardly from the transport position, the improvement comprising a ground-engaging pad having a ground contacting surface, pivot means connecting said paid to the outer end of said arm and means for extending and retracting said arm toward and away from said vehicle and for effecting movement of said arm and pad from (1) said transport position wherein said ground contacting surface is disposed on one side of a plane including said pivot means and said inner end to (2) said support positions wherein said ground contacting surface is disposed on the other side of said plane.
 2. The outrigger of claim 1 including supporting means for said support arm, said inner end being pivotally attached to said support means, and wherein the arm and pad moving means comprises power means pivotally connected to said arm to effect rotation of said arm about said inner end from said transport position to said support positions.
 3. An outrigger support mechanism comprising: A. a frame; B. a substantially horizontally disposed beam telescopingly mounted within said frame; C. an arm pivotally connected to the outer end of said beam; D. a first power means for extending and retracting said beam relative to said frame, and; E. a second power means for pivoting said arm relative to said beam between an upward transport position and downward support positions, each of said first and second power means being independently operable.
 4. The outrigger of claim 3 in which said first and second power means are coplanar.
 5. A load-lifting apparatus including at least one outrigger support mechanism of claim
 3. 6. The outrigger of claim 3 in which said first power means is located within said frame.
 7. An outrigger support mechanism comprising: A. a frame; B. a beam telescopingly mounted in said frame; C. an arm pivotally connected at one end to the outer end of said beam, said arm having a ground-engaging pad including a ground contacting surface on the other end thereof; D. a first power means for extending and retracting said beam relative to said frame; and E. a second power means for pivoting said arm relative to said beam between an upward transport position and downward support positions, said second power means being located with said frame at least when said arm is in the transport position and being operable independent of said first power means wherein said arm is movable between said transport and support positions independent of the position of said beam; when said arm is in said transport position, the ground contacting surface of said pad is disposed on one side of a plane including said arm one end and other end and when said arm is in said support positions, the ground contacting surface is disposed on the other side of said plane.
 8. The outrigger of claim 7 in which said first power means is located within said frame.
 9. The outrigger of claim 8 in which said first and second power means are coplanar.
 10. The outrigger support mechanism of claim 7 in which said beam, said first power means, and said second power means are substantially horizontally disposed.
 11. The outrigger of claim 7 in which said beam is hollow and said second power means is located within said beam.
 12. A load lifting apparatus including at least one outrigger support mechanism of claim
 7. 13. An outrigger support mechanism comprising: A. A frame; B. a beam telescopingly mounted in said frame; C. an arm pivotally connected to the outer end of said beam; D. a first power means for extending and retracting said beam realtive to said frame; E. a second power means for pivoting said arm relative to said beam, independently of the extension position of said beam, from an upward transport position to any of a plurality of operative downward support positions between said transport position and support positions in which said arm is in the maximum downward position.
 14. The outrigger of claim 13 in which said first power means provides for extension and retraction of said beam independently of the position of said arm.
 15. The outrigger of claim 13 in which said beam, said first power means, said second power means, are substantially horizontally disposed.
 16. The outrigger of claim 15 in which said first and second power means are coplanar.
 17. The outrigger support mechanism of claim 13 in which said first power means is located within said frame, and said second power means is located within said beam.
 18. A load lifting apparatus including at least one outrigger support mechanism of claim
 13. 19. An outrigger support mechanism for stabilization of a vehicle, the outrigger comprising a support arm, pivotal means connecting said arm to an arm supporting means, power means for selectively moving said arm between (a) a transport position in which said arm is disposed above a predetermined position of said vehicle and (b) a plurality of operative support positions in which said arm is disposed at different levels below said portion of said vehicle, and laterally between (c) a proximal position in which said arm is adjacent to said vehicle and (d) a distal position in which said arm is remote from said vehicle, and means enabling said power means to move said arm between said transport position and said support positions independent of the lateral position of said arm.
 20. An outrigger support mechanism as defined in claim 19 wherein said power means comprises first reciprocating means attached to said arm supporting means for moving said arm supporting means laterally between said proximal and said distal positions and second reciprocating means attached to said support arm for moving said support arm between said transport and support positions.
 21. An outrigger support mechanism comprising: a. a frame; b. a substantially horizontally disposed beam telescopingly mounted within said frame; c. an arm pivotally connected to the outer end of said beam; d. a ground-engaging pad having a ground contacting surface and being pivotally connected to said arm; e. a first power means for extending and retracting said beam relative to said frame; and f. a second power means for pivoting said arm relative to said beam between an upward transport position wherein said ground contacting surface is disposed on one said of a plane including said pivot means and said outer end of said beam to downward support positions wherein said ground contacting surface is disposed on the other side of said plane, each of said first and second power means being independently operable. 